A Herefordshire farmer is warning of a shortage of blackcurrant squash and jam claiming global warming has affected his crop.
Mr Thompson said he carried out several tests
Edward Thompson, from Ledbury, said he first noticed a mild winter in 1998 meant only half as much fruit grew but he was baffled as to why.
Eight years later he said he has "no doubt" it is due to global warming.
Increasingly mild winters since 1998 has forced him to try a crop from New Zealand which grows in milder climates.
The blackcurrant fruit needs a long, cold winter to enable the buds to develop but only now are farmers directly linking the warmer weather to the problems with their crop.
Mr Thompson told BBC News that he looked as several aspects of the growing process before he felt it was down to climate change.
He said: "It was a huge shock. Not only our long term plans had to be torn up but, all our plans had to be torn up.
"We looked at soil, minerals, and leaf analysis and did not find any answers, we couldn't see what had happened.
"We looked at our pruning techniques and then we found the answer and have no doubt at all that we are right. It is written clearly there, global warming."
Mr Thompson has travelled to several countries to try to source a replacement blackcurrant crop before deciding to plant the New Zealand bushes this winter.